Diagram Interaksi Perancangan Kolom Dengan Tulangan Pada Empat Sisi Berdasarkan Sni 2847:2013 Dan Aci 318m-11

Dalam tulisan ini dibahas perancangan kolom yang disesuaikan dengan SNI 2847:2013 dan ACI 318M-11. Untuk keperluan praktis, dikembangkan diagram-diagram sebagai alat bantu perancangan. Kolom yang ditinjau adalah kolom empat persegi panjang dengan tulangan pada keempat sisinya, di mana masing-masing sisi mempunyai luas tulangan yang sama. Dalam penurunan rumus-rumus dan grafik-grafik, tulangan dianggap sebagai pias baja dengan tebal tertentu yang sesuai dengan luas tulangan masing-masing sisi. Persamaan-persamaan keseimbangan gaya dan momen kemudian diturunkan untuk berbagai diagram regangan dan tegangan yang mungkin terjadi. Sebagai pendekatan, dalam penurunan persamaan, luas tulangan yang ditempati oleh baja desak tidak ditinjau. Diagram-diagram untuk berbagai mutu beton dan baja selanjutnya dibuat untuk memudahkan perancangan kolom. Diagram interaksi dibuat tak-berdimensi, sehingga dapat digunakan untuk berbagai ukuran kolom. Dalam setiap diagram, disediakan beberapa rasio tulangan yang dapat digunakan untuk perencanaan. Diagram interaksi dibuat untuk kuat perlu, kuat nominal dan kapasitas maksimum. Dengan demikian diagram interaksi yang dikembangkan dapat digunakan untuk perencanaan kolom-kolom struktur sebagai kolom pada struktur rangka momen biasa, rangka momen menengah, dan rangka momen khusus menurut peraturan gempa yang berlaku. Pada bagian akhir disajikan beberapa aplikasi penggunaan diagram interaksi yang dibuat sebagai alat bantu perancangan

Sizing and Pre-stressing Force Optimization of Pre-stressed Concrete Beam Using Fast Multi Swarm Optimization

Nowadays, pre-stressed concrete is commonly used in many structural constructions, such as bridge and  building structures. Cross sectional area of the beam can be smaller if pre-stressed concrete beam is used compared to ordinary reinforced concrete one. In this case, it will have cost saving if we can optimized the structures. However, it must have a good technique for obtaining the optimum cross sectional area of the pre-stressed concrete beam, One of the optimization techniques that give a good result for optimization process is fast multi swarm optimization. In this paper, fast multi swarm optimization was used to obtain the optimum cross sectional area and optimum prestressing force of the pre-stressed concrete beam of simply supported condition. This study shows better result compared to the previous research when using similar objective functio

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